One Piece: Robin uses Shigan on Giant Prisoner by SUSHIFREAK101 on DeviantArt

Could Mihawk or Shanks Know Rokushiki? : r/OnePiecePowerScaling

The Rokushiki Techniques Explained

Rokushiki, Wiki

Rokushiki Robin action scene 2 - part 2 by Shinjojin on DeviantArt

Cipher Pol by Dgenris -- Fur Affinity [dot] net

World of Shinjoin! — The Nico Robin: Rokushiki style Project! (part2)

COMO FUNCIONA O ROKUSHIKI DE ONE PIECE?

Honestly Oda probably should have just expanded on Rokushiki instead of creating Haki. He could have definitely made it to where there are techniques that allow you to hit logias and armament

Shigan, Wiki

Rokushiki Robin 32-1 by Shinjojin on DeviantArt